SKU: 44205949516

HP EFI Universal MPI Retrofit Kits - 550-500

Sale price$1777.47 Regular price$1974.97
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Description

HP EFI Universal MPI Retrofit Kits - 550-500Overview: Do you have a Mopar, Ford or other type engine you want to install multi port fuel injection on? No, problem, the Holley HP universal retrofit EFI kits are designed to be used with any V 8 intake manifold. The kit comes with injector bungs and un machined fuel rails so you can modify to fit any single plane 4bbl intake manifold. The HP universal retrofit kits also come with the necessary wiring, ECU, sensors and throttle body. Just select

Overview:

Do you have a Mopar, Ford or other type engine you want to install multi-port fuel injection on? No, problem, the Holley HP universal retrofit EFI kits are designed to be used with any V-8 intake manifold. The kit comes with injector bungs and un-machined fuel rails so you can modify to fit any single plane 4bbl intake manifold. The HP universal retrofit kits also come with the necessary wiring, ECU, sensors and throttle body. Just select the fuel pump and injectors of choice and you are off and running.

Features:

  • NEW V2 SOFTWARE FEATURES
  • “Quick Start” ignition and fueling strategy for LS x Engines
  • Data Logger. Scalable axes, Smoothing, Multiple graph view ability, Pre-defined notes fields and many more
  • Strip Chart Real-Time Data Viewer
  • Integrated Boost Control - Boost vs Time, Boost vs Gear (Time or RPM), Boost vs RPM, Boost vs Speed, Launch control. Boost launch builder, Over-boost safeties, Boost scramble
  • Traction Control - Power reduction via timing, nitrous percentage or boost (Requires Davis Technologies Holley Module)
  • “Quick Start” fueling for all engines
  • Option for VE based fueling strategy
  • Fuel Map and Learn Function Smoothing
  • Configurable User Password Protection
  • Fully Configurable lap top Gauge Panel
  • FEATURES
  • Optional 5.7” full-color touchscreen LCD allows easy on-the-fly tuning,data-logging or can be used as an easy to see graphical gauge panel
  • Eight sequentially driven 8:2 peak and hold injector drivers, capable of driving up to 16 low or high impedance injectors as a standard feature. Multiple staged injector strategies
  • Eight channel Distributorless Ignition (DIS)outputs capable of directly driving “Smart” ignition coils or Holley DIS coils. Will drive 2 wire coils with the addition of PN 554-112 high current coil driver module
  • Plug and Play control of factory GM 24x and 58x LSx engines
  • Integrated single channel wide band oxygen sensor control. Works with NTK or Bosch sensors
  • Internal data-logging standard with a huge 2GB of memory
  • 4 Stage progressive nitrous control
  • Turbo boost control
  • Integrated water/methanol injection control
  • Self-tuning fuel table strategy greatly simplifies tuning process
  • Individual cylinder fuel and spark control allows you to unlock your engine’s potential
  • Works with 4, 6, 8 cylinder engines
  • Unique lb/hr based fueling strategy greatly simplifies and commonizes tuning
  • Advanced idle, closed loop, and enrichment strategies allow for very stable operation
  • ECU is fully potted and can be mounted in the engine compartment or interior
  • Sealed automotive and marine grade connectors
  • Allows for use of common OEM sensors as well as customer sensor calibration input
  • Ignition Plug and Play with GM 24x and 58x LSx engines, GM HEI, Ford TFI, magnetic and hall effect trigger, and other ignition systems. New Plug and Play applications in process. Custom settings can be configured to allow many other applications
  • 1-5 Bar MAP sensor capability
  • Two channel knock control sensor Inputs for both one or two wire knock sensors
  • Dedicated fuel and oil pressure inputs
  • Controls both stepper and PWM Idle Air Control (IAC) motors
  • Speed density, Alpha-N, or combination fueling strategies
  • 4 Programmable high or low Pulse Width Modulated (PWM) outputs and 4 fully configurable inputs can be configured for use
  • 4 Stage nitrous oxide control
  • Fully featured nitrous control eliminates the need for a separate nitrous controller device
  • Can be configured “Wet” or “Dry” with closed loop feedback
  • Progressive control based on time, RPM, or boost, requires part # 554-111
  • Lean or rich safety cutoff
  • Full timing retard/control configurability per stage based on RPM or time
  • Integrated Water/Methanol injection control
  • Uses Holley Water/Meth solenoids specially designed and calibrated for use with this EFI system to allow the user to enter Water/Meth flow as a percentage of fuel injector flow for Water/Meth tu

 

Application:

Year Make Model Submodel Engine Size
Universal

 

Specs:

Brand Holley EFI
Emission Code 3
Ignition Type CD Ignition (No Timing Control)
Injector Connector Jetronic / Minitimer (Bosch)
Product Type Universal Multi Port
Terminator LS Options Fuel, Spark
Shipping Notes
  • Free Standard Shipping on $100+ Orders to the USA.
  • Except Preorder products are shipped in 48 hours.
  • Delivery to the USA:
  1. Standard Shipping : 3-10 business days
  • If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
  • We offer a 30-day return/exchange service after receiving.
  • Final sale items are not eligible for returns or exchanges.
  • To process your return/exchange, please contact us at [email protected]
  • Please click here for more details>>> Return & Exchange Policy
SKU: 44205949516

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4.0 ★★★★★
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The Fingernail Reviewer
Phoenix, US
★★★★★ 4
Pillowriffic
Color: White, Size: Queen (Pack of 2), Color: White, Size: Queen (Pack of 2)
These pillows are exactly as described, I would say they are softer than I expected but still very good. They come compressed so it will take an hour or so for them to fill up so you will want to open these before bedtime. All in All if you are looking for a reasonably priced pillow that will last a couple of months I would recommend these.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 7, 2026
N
Verified Purchase
NF-Calif
Massapequa, US
★★★★★ 5
Great buy
Color: White, Size: Queen (Pack of 2)
I was very skeptical about buying pillows online. I am pleasantly thrilled with these pillows. They are great quality. They maintain their shape by simply shaking occasionally if needed. The fabric is really soft to the touch. They don't go flat after a few uses. I've had them for almost 6 months. I waited to review to make sure they didn't disappoint.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on June 6, 2026
P
Verified Purchase
Philly Gurl
Los Angeles, US
★★★★★ 5
LOVE THEM!!! SAVED MY NECK!!!
Color: White, Size: Queen (Pack of 2)
Hallelujah!!! After spending so much money on pillows that didn't work for my aching neck and shoulders, I finally found pillows that works for me and I am SOOOOOO excited. I had my 1st night of comfortable sleeping after years of restless, painful nights. These pillows are the BOMB! I kid you not. I have spent hundreds of dollars on pillow to no avail. I mean, the expensive hotel pillows that were suppose to make you feel as if you're sleeping on clouds made my neck stiff and painful. Let's not talk about that "infamous pillow: advertised on the infomercial that was suppose to be the #1 pillow to fight against neck and back pain. Shhhh, we won't say the name but uh....TRASH. Ok, I'm back. Lost it there for a moment thinking of all the money I wasted on all those pillows that claimed to be "THE PILLOW." LOL..what a joke. So, anyway back to what I was saying about this pillow beauty. The very 1st night I slept on it, I'll admit I was skeptical when I laid down. Scared I was going to wake up with a sore neck and headache to go along with it. I tore the package open, let the pillow inflate, fluffed them with my hands and allowed them to sit for a few hours. I didn't wait the allotted time suggested because I was too anxious to try them and it was almost my bed time. So, excitedly I jumped in bed, laid my head down on the pillow and immediately thought, "oh no, these are too soft. This will not work." I just knew I would wake up to a sore neck. Cautiously, I laid down and waited to drift off, dreading waking up the next morning with a stiffer. (LOL) To my surprise I actually slept all night too. I usually would wake up like a thousand times fighting with repositioning the pillow to find my comfort zone. WOW, not that night. I slept like a baby and wait for it.....I woke up the next morning with NO PAIN! Hallelujah! I couldn't believe it. I was literally pain free in my neck and did not have a headache from the strain on my neck, shoulders and back. Man, is this really happening, I asked myself. This just can't be real. Wake, wake girl. You are dreaming. But nope. I was fully awake and with a pain free neck and shoulders. I jumped up and started getting ready for my day. I finally found the pillow that I wish I had found years ago. Could have saved so much $ from going down the drain. I am SO thankful to all the reviews that I read that shared their positive experience and encouraged me to purchase for myself. I am SOOOO GLAD I took a chance and brought these little beauties. They saved my neck and my sanity. Thank you EIUE Hotel Collection for inventing the pillow that is reasonably priced and that does the job it's intended to do. Allow people to have a good nights rest WITHOUT neck, shoulder and back pain. Your Rock! This is a real review and I am a real person.
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Reviewed in the United States on February 15, 2025
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Verified Purchase
Amazon Customer
Belleville, US
★★★★★ 3
Flat
Color: White, Size: Queen (Pack of 2)
They are long pillows but definitely flat, I tried and tried to fluff them up and they are about like the $3 Walmart pillows. I will be returning these
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Reviewed in the United States on May 28, 2026
B
Verified Purchase
Betsy Poo
Phoenix, US
★★★★★ 5
Holy Wow!
Color: White, Size: Queen (Pack of 2)
These pillows are so fluffy and material is really soft. They came vacuumed packed. I thought well this will be a return for sure. Followed the directions and placed them in my dryer for 15 minutes. Could not believe how big and fluffy they were. My company always ask for the link and I have ordered them for family members and for myself 4 times. Mine I’ve had over a year and have kept their shape and fluffiness. If you like a fluffy pillow…this is the one. They are the best!!!
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 7, 2026

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